I have seen this one in the trails section and it sounds like a really nice, relaxed place to go mountain biking - were there not that note about it being closed by the YMCA.
The note is from 2011, so I would like to ask if there was any development since then to get it open again? It sounds really fun and would be sad if it was closed for us mountain bikers.

*edit: I just saw this came under advocacy, if it better fits into the trail section of the forum, please move it there. Sorry for the convenience.

By HK standards the ex Lamma Quarry is about the best beginner trail around and its mostly spider free during the summer which is a bonus on Lamma.

Sadly, its now in the hands of the YMCA who obtained it through some kind of subterfuge. They have fenced off the site and you must beg them to get in somehow. No one on the island had a clue that this was in the works and the govt did not post their intentions near the entrance to the quarry either (the govt lands dept drone explained that it was posted in Sok Kwu Wan on an A4 sheet somewhere)...

So the situation has not changed and they have not opened it up again in the meantime.
I will probably try out the other trails on Lamma and ride by the YMCA to see if I can talk to someone and see if they can open up the location at least when asked politely. =) Cheers!